New technique can charge EV battery in just 10 minutes

“The need for smaller, faster-charging batteries is greater than ever,” said Chao-Yang Wang, the William E. Diefenderfer Professor of Mechanical Engineering at Penn State and lead author on the study. “There are simply not enough batteries and critical raw materials, especially those produced domestically, to meet anticipated demand.”

If new car sales are going to shift to battery-powered electric vehicles (EVs), Wang explained, they’ll need to overcome two major drawbacks: they are too slow to recharge and too large to be efficient and affordable. Instead of taking a few minutes at the gas pump, depending on the battery, some EVs can take all day to recharge.

“Our fast-charging technology works for most energy-dense batteries and will open a new possibility to downsize electric vehicle batteries from 150 to 50kWh without causing drivers to feel range anxiety,” said Wang, whose lab partnered with State College-based startup EC Power to develop the technology. “The smaller, faster-charging batteries will dramatically cut down battery cost and usage of critical raw materials such as cobalt, graphite and lithium, enabling mass adoption of affordable electric cars.”

According to Wang, the technology utilises internal thermal modulation, an active approach to temperature control that optimises battery performance. Batteries function most effectively within a specific temperature range, not too hot and not too cold. Maintaining batteries at the ideal temperature has posed a significant hurdle for battery engineers. In the past, they have relied on external, cumbersome heating and cooling systems to regulate battery temperature, resulting in slow response times and substantial energy wastage, Wang explained.

In a departure from conventional methods, Wang and his team opted for an internal approach to temperature regulation within the battery. They devised a novel battery structure incorporating an ultrathin nickel foil as the fourth component alongside the anode, electrolyte, and cathode. This nickel foil serves as a catalyst, autonomously adjusting the battery's temperature and reactivity. As a result, this innovation enables rapid 10-minute charging for virtually any electric vehicle (EV) battery.

“True fast-charging batteries would have immediate impact,” the researchers write. “Since there are not enough raw minerals for every internal combustion engine car to be replaced by a 150kWh-equipped EV, fast charging is imperative for EVs to go mainstream.”

The study’s partner, EC Power, is working to manufacture and commercialize the fast-charging battery for an affordable and sustainable future of vehicle electrification, Wang said.